using System;
using System.Collections;

using Org.BouncyCastle.Asn1;

namespace Org.BouncyCastle.Asn1.Icao
{
	/**
	* The DataGroupHash object.
	* <pre>
	* DataGroupHash  ::=  SEQUENCE {
	*      dataGroupNumber         DataGroupNumber,
	*      dataGroupHashValue     OCTET STRING }
	*
	* DataGroupNumber ::= INTEGER {
	*         dataGroup1    (1),
	*         dataGroup1    (2),
	*         dataGroup1    (3),
	*         dataGroup1    (4),
	*         dataGroup1    (5),
	*         dataGroup1    (6),
	*         dataGroup1    (7),
	*         dataGroup1    (8),
	*         dataGroup1    (9),
	*         dataGroup1    (10),
	*         dataGroup1    (11),
	*         dataGroup1    (12),
	*         dataGroup1    (13),
	*         dataGroup1    (14),
	*         dataGroup1    (15),
	*         dataGroup1    (16) }
	*
	* </pre>
	*/
	public class DataGroupHash
		: Asn1Encodable
	{
		private readonly DerInteger dataGroupNumber;
		private readonly Asn1OctetString dataGroupHashValue;

		public static DataGroupHash GetInstance(
			object obj)
		{
			if (obj is DataGroupHash)
				return (DataGroupHash)obj;

			if (obj != null)
				return new DataGroupHash(Asn1Sequence.GetInstance(obj));

			return null;
		}

		private DataGroupHash(
			Asn1Sequence seq)
		{
			if (seq.Count != 2)
				throw new ArgumentException("Wrong number of elements in sequence", "seq");

			this.dataGroupNumber = DerInteger.GetInstance(seq[0]);
			this.dataGroupHashValue = Asn1OctetString.GetInstance(seq[1]);
		}

		public DataGroupHash(
			int				dataGroupNumber,
			Asn1OctetString	dataGroupHashValue)
		{
			this.dataGroupNumber = new DerInteger(dataGroupNumber);
			this.dataGroupHashValue = dataGroupHashValue;
		}

		public int DataGroupNumber
		{
			get { return dataGroupNumber.Value.IntValue; }
		}

		public Asn1OctetString DataGroupHashValue
		{
			get { return dataGroupHashValue; }
		}

		public override Asn1Object ToAsn1Object()
		{
			return new DerSequence(dataGroupNumber, dataGroupHashValue);
		}
	}
}
